Carburetor



0431:.V 11, 1932. F, H HElTGER 1,881,560

GARBURETOR Filed July 21. 1927 3 Sheets-Sheet l m, a?. S14/manto@MAE/76.5%?,

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F. H. HEITGER CARBURETOR Filed July 21, 1927 3 Sheets-Sheet 2 aan# 3 Aj.Ob j 7 @Norway Patented Oct. 11, 1932 FRANK E. HEITGER, OF FLINT,'MICHIGAN CARBURETOR Application led July 21,

This invention relates to carburetors, and more particularly toimprovements in the choke valve usually provided in the carburetor airintake, and the invention has for one of its objects to provide meansfor automatically regulating the choke valve so as to j insure a supplyof uniformly rich mlxture in the interval from the moment the engine isstarted, until it is brought up to its nor- -"1 mal 'operatingtemperature, the automatic regulation of the valve being combined wlth amanually adjusting device for varying the limits of the automaticcontrol'.

A further object is the'provision of an 5 automatic regulating deviceemploying a spring as an essential element in the regulation of thevalve.

Referring to the accompanying drawings,

wherein an approved embodiment of the invention is illustrated:

Fig. 1 is a side elevation of a conventional carburetor illustrating theinvention applied thereto,

Fig. 2 is a section on the line 2-2 of Fig. 1',

5 Figures'3 and 4 are diagrammatic views showing portions of theregulating device,

Fig. 5 is a fragmentary side elevation of a carburetor, illustratingamodiication of the invention, and

l0 Fig. 6 is a similar view of a further modiication.

Referring to the drawingsin detailnum eral 5 indicates a lconventionaltype of carburetor including a throttle control arm 6,

5 fuel reservoir 7, and air intake 8 in which the shaft 9 supporting thechoke valve 10 is journalled.

According to the present invention, the shaft 9 is located in a planebelow the-axis `=0 of the air intake 8, in order that the differentialpressure active on the valve, incident to the air being drawn throughthe inlet, normally tends to open the valve. Externally of the air inlet8, an arm 11 is secured 5 to the supporting shaft 9, and carries at itsouter end, a swlvelly mounted slide collar 12 receiving the manuallyoperable choke rod 13, which, as will be understood, is extended to apoint within convenient reach 0 of the operator of the engine.

1927. Serial No. 207,488.

' ulation of the valve is ineffective.

An adjustable abutment 17, secured in place by a set screw 1B, orequivalent device. 65 is secured to the extremity of the rod 13, and anexpansion spring 19 confined between said abutment and the slide collar12, normally tends to so displace the arm 11 with respect to the rod 13,as to resiliently retain the valve either in closed position, or in suchnear closed position as the rod 13 will admit, owing to engagement ofthe slide collar 12 with the stop collar 14.

According to modern practice in the construction and design ofcarburetors, the choke valve when partially closed, so as to supply amixture, sufficiently-rich in li uid fuel as to afford proper combustiono an engine during the warming up period, for 86 a certain position ofthe throttle is ineffective in maintaining uniformity' of the proportionof the liquid fuel at other positions of the throttle, than that forwhich the choke valve was originally adjusted, and hence the fuelmixture 1s of the improper proportion and the vengine fails to fireregularly.

The present invention, however, overcomes this objection toA known t pesof choke valves for the reason hereina er more fully explained, and inoperation, when the engine is initially started in a cold condition,thel choke valve 10 is positively retained in closed position byaffecting the adjustment of the rod 13 to supply an exceedingly richmixn ture for initial starting purposes.4 Thereafter, the rod 13 isadjusted to the position shown in Fig. 3, so as to permit of a limitedopening movement of the throttle 10, the extent of such opening movementbeing dewhen the valve is closed, is so disposed as termined by theoperator according to the' suctlon effect acting thereon. For instance,when the engine is running at relativel low speed, and the pressuredil'erencev o the valve is correspondingly low, the spring 19 actingagainst the pressure of the incoming air, moves the valve toa positionfarther closed, whereas when the pressure effect on the valve increases,the latter is opened against the tension of the spring to admit agreater quantity of air. When the engine has been heated sufl'lcientlyfor normal running, the rod 13 is manually displaced suiiciently topositively maintain the valve 10 in opened position against the stop 20.

According to the modification illustrated in 5, the valve 10 constructedand mounted on the shaft 9 as previously described, is mounted on theintake of the carburetor andthe arm 21 thereof is connected with acontractile spring, the tension of which normally acts to move the valveto closed-position against the pressure effect of the incoming air. Aswill be understood, the extremity of the spring 22, opposite the arm 21,is suitably connected with a stationary part of the carburetor.

The opening movement of the valve is variably limited by a stop collar23, adjustably mounted on the choke rod 24 which latter passes throughthe extremity of the arm 21. A second stop collar 25, coacting with thearm 21 to positively maintain the valve in opened position, is alsoadjustably mounted on ,the rod- 24.

The operation of this form of the invention is substantially the same asthat described in connection with the form of the invention firstillustrated, except-that the spring normally tending to close the valveinstead of coacting directly between the arm and choke control rod isinterposed between the carburetor body and valve arm.'

The` arrangement according to the modification illustrated in Fig. 6 issubstantially the same as that illustrated in Figs. 1 to 4, except thatthe arm 11, instead of being arranged to extend upwardly from the shaft9 to extend downwardly from said shaft when the valve is closed.

In view of the similarity of the construction and arrangement of parts,the same reference numerals have been used in Fig.v 6 as those employedin Figs. 1 to 4 inclusive.

As proposed in another of my pending applications, the spring in eitherof the forms of the invention illustrated, may be constituted by thermosensitive elements, which, whenV exposed to the exceedingly lowtemperatures, increase the tension of the proper quantity of airaccording to theA spring to such extent as to offer greater resistanceto the opening movement of the in a position in proximity with theengine.

is affected by the heat radiated from the latter, as theengine is warmedto normal working temperature, and thus the tension of the spring isgradually reduced to normal, as the engine temperature approaches a moremoderate thermal condition.

What I claim and desire to secure by Letters Patent is: 1. In acarburetor, an air inlet, a choke valve in said inlet opened in responseto incoming air, a manually operable choke valve rod, stop collarsarranged in spaced relation on said rod, an arm on said valve movablebetweenv'said stop collars, and spring means interposed between the rodand arm, normally tending to move the valve to closed position.

2. In a carburetor, an air inlet, a choke valve in said inlet opened inresponse to incoming air, a manually operable chok'e valve rod, stop'collars arranged in spaced relation on said rod, an arm on said valvemovable between said stop collars, spring means interposed Ibetween therod and arm normally tending to move the valve to closed position, andmeans adjustably securing the stop collars on said rod.

3. In a carburetor, an air inlet, a choke valve in said inlet opened inresponse to incoming air, a manually operable choke valve rod, stopcollars arranged in spaced relation on said rod, an arm on said valvemovable between said stop collars, spring means interposed between therod and arm normally tending to move the valve to closed position, andmeans for varying the tension of said spring means.

4. In a carburetor having an air inlet, a

valve mounted therein so as to be operated by suction, said valve beingnormally out of action, except when warming up, spring means to resistthe opening of the valve, and means to, at will, from a distant point,regulate said spring, and also to positively hold said valve closed, andwide open out of action.

5. In a. carburetor having an air inlet, a valve mounted therein so asto be operated by suction, said valve being normally out of action,spring means to resist the opening of the valve, and means to, at will,regulate said spring, and also positively hold said valve closed, andwide open out of action.

6. In a carburetor having an air inlet, a valve mounted therein so thatit may be operated by suction, said valve during normal operation of thecarburetor being positively held Wide open and out of action, meansoperable from a dista-nt point to positively close said valve forstarting the motor to which the carburetor is attached and to positivelyopen it wide, said last mentioned means being adapted to adjust a springwhich comes into action When the -valve is released from a positiveclosed position to yieldably oppose the valve opening by suction.

In testimony whereof-I hereunto aix my signature.

FRANK H. HEITGER.

